ORLANDO, Fla. -- J.R. Smith had the Garden buzzing Thursday night -- and his teammates up waving towels and their arms for the fans to get even louder.

Smith cut backdoor and leaped, but Pablo Prigioni threw a lob that was around Smith's waist. He caught it and in one motion rifled the ball up and over his head, throwing it down one-handed with his back to the basket.

"He does some amazing things," Tyson Chandler said. "He's a freak of nature."

The eye-popping slam punctuated the Knicks' blowout win over the Spurs and another strong game for Smith, a leading candidate for Sixth Man of the Year.

Clippers super-sub and former Knick Jamal Crawford might be ahead at this point, but Smith is making a strong case. The Knicks wouldn't be 22-10 heading into Saturday night's game against the Magic without him.

"That was the whole idea coming into this season is putting him in that position as a guy coming off the bench that could lead the league or score a lot of points off the bench," Mike Woodson said. "We put him in that position to do that. I think he's starting to step up."

When he wasn't named a starter in training camp, Smith was upset. But he has embraced his role as the Knicks' No. 2 scorer behind Carmelo Anthony, especially with Amar'e Stoudemire out the first 30 games and Raymond Felton now sidelined.

Smith is averaging 16.6 points, one-tenth of a point ahead of Crawford and leading all reserves before Friday night's action. Smith has scored at least 20 points in his last five games, including the winning basket in Phoenix on Dec. 26. He's averaging 25.6 points in that span.

"He seems locked in, focused," said Anthony, who has been Smith's teammate for parts of seven seasons with the Nuggets and Knicks. "That's the J.R. I know. I've seen the potential all along. It's nothing new for me."

Stoudemire added: "He's playing great. . . He's focused. He's dedicated to the game. He's putting forth the effort. I see him working after practice."

"They've been working with me after practices, trying to get my feet ready, get ready to score the ball and not so much worry about taking shots, but taking good shots," Smith said.

Before this season, Smith always could score but never was known as someone who consistently took good shots. He has been more under control this season than ever before in his nine-year career, and he's showing he can do more than score. In his last seven games, Smith is averaging 7.0 rebounds, 3.9 assists and 2.1 steals.

"He's being more patient about his play and he's trying to do it on both ends of the floor," Woodson said. "That's what's so nice about it. He's not just committing to the offensive end. He's trying to defend, rebound, he's sacrificing the ball when he has to. He's playing an all-around good game, I think."

There still are 50 games left, but Smith is averaging career bests in scoring, rebounding (5.2) and assists (2.8). He also has hit the first two game-winning shots of his career, with the first against Charlotte on Dec. 5. But the dunk could become one of the more memorable plays of the season for Smith and in the NBA.

"I jumped so early," Smith said. "I went backdoor and he threw it, it was kind of low, so I didn't think I was going to dunk it, to be honest with you, as high as I jumped."